There are actually a lot of changes in this 2nd edition. In addition to all of the changes of bringing the examples up to Yii version 1.1.12, this 2nd edition removes all of the test-driven-development (TDD) approach that was so strictly followed in the first edition. This was based on a lot of reader feedback, which indicated this TDD approach was somewhat of an obstacle to being able to focus on the framework specific features. Also, this 2nd edition consolidated chapters 3 and 4 of the 1st edition into the single chapter 3 of this 2nd edition. So, this accounts for some of the saving of trees in the 2nd edition.

There are actually a lot of changes in this 2nd edition. In addition to all of the changes of bringing the examples up to Yii version 1.1.12, this 2nd edition removes all of the test-driven-development (TDD) approach that was so strictly followed in the first edition. This was based on a lot of reader feedback, which indicated this TDD approach was somewhat of an obstacle to being able to focus on the framework specific features. Also, this 2nd edition consolidated chapters 3 and 4 of the 1st edition into the single chapter 3 of this 2nd edition. So, this accounts for some of the saving of trees in the 2nd edition.

I can only agree with your reasoning for removing the TDD stuff. I've read the entire book a year ago. While I did enjoy the exposure to TDD I think that, just as you said, it takes the focus out of Yii, which should be the main focus of the reader. Kudos for it.